Using the neutron time-of-flight facility at the Indiana University Cyclotron Facility we have studied (p, n) reactions on the light nuclei Li, ' "B,and ' ' C. Double differential cross sections have been measured between Hi, b=0' and 50' in 5' intervals, at E"=186MeV. Contributions of the quasifree reaction in the giant resonance region are estimated. Energy spectra of EL=1 transitions have been extracted using multipole decomposition analysis. The resulting EL=1 spectra are compared with results of photonuclear reactions.Empirical results are also compared with distorted wave impulse approximation calculations. PACS number(s): 25.40.Ep, 27.20.+n, 24.70.+s

Neutrons are unique particles to probe samples in many fields of research ranging from biology to material sciences to engineering and security applications. Access to bright, pulsed sources is currently limited to large accelerator facilities and there has been a growing need for compact sources over the recent years. Short pulse laser driven neutron sources could be a compact and relatively cheap way to produce neutrons with energies in excess of 10 MeV. For more than a decade experiments have tried to obtain neutron numbers sufficient for applications. Our recent experiments demonstrated an ion acceleration mechanism based on the concept of relativistic transparency. Using this new mechanism, we produced an intense beam of high energy (up to 170 MeV) deuterons directed into a Be converter to produce a forward peaked neutron flux with a record yield, on the order of 10(10)  n/sr. We present results comparing the two acceleration mechanisms and the first short pulse laser generated neutron radiograph.

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We present a full characterization of a short pulse laser-driven neutron source. Neutrons are produced by nuclear reactions of laser-driven ions deposited in a secondary target. The emission of neutrons is a superposition of an isotropic component into 4p and a forward directed, jet-like contribution, with energies ranging up to 80 MeV. A maximum flux of 4.4 Â 10 9 neutrons/sr has been observed and used for fast neutron radiography. On-shot characterization of the ion driver and neutron beam has been done with a variety of different diagnostics, including particle detectors, nuclear reaction, and time-of-flight methods. The results are of great value for future optimization of this novel technique and implementation in advanced applications. V

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